Cancer survivors are at increased risk, not only for progressive and recurrent disease, but also other cancers, cardiovascular disease, diabetes, osteoporosis, and functional decline. Lifestyle interventions to improve dietary and physical activity behaviors, and smoking cessation, have the potential to improve the overall health and quality of life of this vulnerable population. Studies on overall health and physical function from 1966 and beyond regarding the impact of behavioral interventions that used randomized and controlled designs were identified through MEDLINE and PubMed searches. Published reports currently exist for 22 exercise interventions, 11 diet-related interventions (excluding those limited to dietary supplements or single nutrients), two diet and exercise interventions, and 10 behavioral-based smoking cessation interventions. Although many interventions have been successful in promoting behavioral change and have resulted in improvements in various health-related outcomes, more research is needed to determine the key components of interventions that are able to produce the greatest behavioral change and the most favorable health-related benefits. The oncology care provider can play a pivotal role in improving the long-term health of cancer survivors by (1) being aware of opportunities to encourage healthful behaviors (ie, smoking cessation, weight control, and increased physical activity); (2) vigilantly tracking long-term effects among cancer survivors and exploring whether they are amenable to intervention; (3) staying abreast of current health behavior guidelines for cancer survivors and existing resources for professional and patient education; and (4) supporting and contributing to efforts aimed at primary and tertiary prevention research. © 2006 by American Society of Clinical Oncology.